1. Field of the Invention
This invention is directed to a process and an apparatus for continuous wrapping of palletized load with stretch-wrap film, which load is placed on a fixed base.
2. Description of Related Art
In the wrapping operation the powered machine conveys a reel of film around the load at some distance from it, so that the film is continuously wrapped around said palletized load or any bulky object, as it unwinds from the reel.
An apparatus for continuously wrapping a palletized load is previously known from European patent application No. 82 10 6492.0 by the same applicant. This apparatus comprises a carriage conveying a reel of stretch-wrap film, which carriage rests in turn on two sets of wheels with their axes converging at a point corresponding to the point at which a vertical axis through the palletized load to be wrapped intersects the floor. In its circular motion said carriage is guided by a steering unit of flat configuration, resting on the same floor on which the load lies, the steering unit being concentrical with the palletized load to be wrapped.
Although, in practice, this last mentioned machine has provided excellent results, it has however the disadvantage of requiring for the wrapping operation said carriage steering unit, with the resulting need to prearrange the palletized load in the center of said steering unit.
U.S. Pat. No. 4,095,395 describes a carriage for supporting a reel of stretch-wrap film. Said carriage comprises a means for steering it on a floor around the load to be wrapped, a feeler means projecting towards said load for contacting its surface, a means of support for the vehicle to allow free movement around the load and a unit for holding and wrapping the film around the load, as the vehicle freely travels along a path on the floor around said load for the required number of times. The path around the load is determined by the outer contour of the load.
With this vehicle, if the load has an irregular contour and especially any recess, the contact feeler may become stuck in said recess causing the vehicle to stop or, in any case, is more likely to break. This is also the case with platforms of irregular shape.